Blaziken

Mega Blaziken has a great Attack stat and the access to Speed Boost, enabling it to outpace Pokemon like Mega Metagross and Mega Lopunny. Thanks to its Fire / Fighting typing, it can take care of many Steel- and Grass-types like Magearna, Genesect, Heatran, and Serperior and bulky Pokemon like Porygon2 and Type: Null with High Jump Kick. However, Mega Blaziken struggles with walls like Mega Slowbro and Clefable, which are able to tank it's hits thanks to their massive bulk. Mega Blaziken also suffers against bulky Water- and Ground-types like Tapu Fini, Mega Gyarados, Landorus-T, Garchomp, and Zygarde-C because they can survive Mega Blaziken's attacks and OHKO it with their super effective moves. Mega Blaziken has to rely on Protect to get a Speed boost. This allows Substitute users like Torrent Greninja to play mind games and use Substitute on the Protect turn to win the matchup.